Congenital heart diseases (CHD) are the most common serious congenital anomalies and the leading cause of death due to birth defects. Clinical practice relying on physical examination of the newborn before discharge from the nursery often misses newborns with critical CHD (CCHD), which can lead to death or long-term morbidities. Using pulse oximetry (PO) can improve clinical examination by detecting CCHD that would otherwise be missed. In September 2011, DHHS decided to add pulse oximetry screening in the right hand and one foot for CCHD detection to the Recommended Uniform Screening Panel. Hospitals throughout the US are now working expeditiously to implement PO screening programs so that all newborns will have PO screening prior to nursery discharge. However, there is no PO device for newborns and many are concerned about the high false screening rates and cost using current pulse oximeters. The goal of this project is to develop a pulse oximeter for newborn screening (PONS) that has many advantages: 1) simple to use thus reducing training time and cost; 2) much shorter procedure time; 3) better signal quality from multiple sensors; 4) lower cost from lower false positive rate and elimination of disposable sensors; less patient distress. We aim to develop a PONS prototype with multiple sensors for newborn screening. Our PONS device will slip over the infant's hand or foot, and a unique combination of algorithms and sensor placement will provide accurate, reproducible, SpO2 reading in less than two minutes. A single use interior cover of the device will be used to prevent infection, enhance signal acquisition, and reduce the cost of screening. After initial bench top testing, safety and efficacy, the PONS will be evaluated in 5 adults first, then in 5 newborns with co-oximetry validation. We will then conduct a clinical effectiveness study on newborns to benchmark PONS readings against conventional readings with a commercial pulse oximeter. We will recruit 100 newborns from the nursery at Harbor-UCLA Medical Center. All newborns will have pulse oximeter checks by a commercial device and the PONS at 24 hours of life. The primary expected outcome is a reduction of total procedure time with the PONS device. We will also compare the following parameters-SpO2, signal quality, time for signal acquisition, cost, and user feedback. In Phase II of this project, the Phase I clinical will be used to re-engineer th device and conduct a clinical trial evaluating the cost-effectiveness of the PONS for CCHD detection in newborns during Phase II.